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Nature Communications Mar 2019The genome of the thermophilic bacterium, Aeribacillus pallidus 8, encodes the bacteriocin pallidocin. It belongs to the small class of glycocins and is...
The genome of the thermophilic bacterium, Aeribacillus pallidus 8, encodes the bacteriocin pallidocin. It belongs to the small class of glycocins and is posttranslationally modified, containing an S-linked glucose on a specific Cys residue. In this study, the pallidocin biosynthetic machinery is cloned and expressed in Escherichia coli to achieve its full biosynthesis and modification. It targets other thermophilic bacteria with potent activity, demonstrated by a low minimum inhibitory concentration (MIC) value. Moreover, the characterized biosynthetic machinery is employed to produce two other glycopeptides Hyp1 and Hyp2. Pallidocin and Hyp1 exhibit antibacterial activity against closely related thermophilic bacteria and some Bacillus sp. strains. Thus, heterologous expression of a glycocin biosynthetic gene cluster including an S-glycosyltransferase provides a good tool for production of hypothetical glycocins encoded by various bacterial genomes and allows rapid in vivo screening.
Topics: Amino Acid Sequence; Anti-Bacterial Agents; Bacillaceae; Bacteriocins; Cloning, Molecular; Disulfides; Escherichia coli; Genes, Bacterial; Glycopeptides; Microbial Sensitivity Tests; Multigene Family; Protein Structure, Tertiary; Sequence Homology, Amino Acid
PubMed: 30846700
DOI: 10.1038/s41467-019-09065-5 -
Microbiology and Molecular Biology... Jun 2004Gene expression in members of the family Bacillaceae becomes compartmentalized after the distinctive, asymmetrically located sporulation division. It involves complete... (Review)
Review
Gene expression in members of the family Bacillaceae becomes compartmentalized after the distinctive, asymmetrically located sporulation division. It involves complete compartmentalization of the activities of sporulation-specific sigma factors, sigma(F) in the prespore and then sigma(E) in the mother cell, and then later, following engulfment, sigma(G) in the prespore and then sigma(K) in the mother cell. The coupling of the activation of sigma(F) to septation and sigma(G) to engulfment is clear; the mechanisms are not. The sigma factors provide the bare framework of compartment-specific gene expression. Within each sigma regulon are several temporal classes of genes, and for key regulators, timing is critical. There are also complex intercompartmental regulatory signals. The determinants for sigma(F) regulation are assembled before septation, but activation follows septation. Reversal of the anti-sigma(F) activity of SpoIIAB is critical. Only the origin-proximal 30% of a chromosome is present in the prespore when first formed; it takes approximately 15 min for the rest to be transferred. This transient genetic asymmetry is important for prespore-specific sigma(F) activation. Activation of sigma(E) requires sigma(F) activity and occurs by cleavage of a prosequence. It must occur rapidly to prevent the formation of a second septum. sigma(G) is formed only in the prespore. SpoIIAB can block sigma(G) activity, but SpoIIAB control does not explain why sigma(G) is activated only after engulfment. There is mother cell-specific excision of an insertion element in sigK and sigma(E)-directed transcription of sigK, which encodes pro-sigma(K). Activation requires removal of the prosequence following a sigma(G)-directed signal from the prespore.
Topics: Bacillus subtilis; Bacterial Proteins; Cell Compartmentation; Chromosomes, Bacterial; DNA, Bacterial; Forecasting; Gene Expression Regulation, Bacterial; Genes, Bacterial; Regulon; Sigma Factor; Spores, Bacterial
PubMed: 15187183
DOI: 10.1128/MMBR.68.2.234-262.2004 -
International Journal of Molecular... Feb 2021Methanol dehydrogenase (Mdh), is a crucial enzyme for utilizing methane and methanol as carbon and energy sources in methylotrophy and synthetic methylotrophy....
Methanol dehydrogenase (Mdh), is a crucial enzyme for utilizing methane and methanol as carbon and energy sources in methylotrophy and synthetic methylotrophy. Engineering of Mdh, especially NAD-dependent Mdh, has thus been actively investigated to enhance methanol conversion. However, its poor catalytic activity and low methanol affinity limit its wider application. In this study, we applied a transcriptional factor-based biosensor for the direct evolution of Mdh from (Lxmdh), which has a relatively high turnover rate and low value compared to other wild-type NAD-dependent Mdhs. A random mutant library of was constructed in and was screened using formaldehyde-detectable biosensors by incubation with low methanol concentrations. Positive clones showing higher fluorescence were selected by fluorescence-activated cell sorting (FACS) system, and their catalytic activities toward methanol were evaluated. The successfully isolated mutants E396V, K318N, and K46E showed high activity, particularly at very low methanol concentrations. In kinetic analysis, mutant E396V, K318N, and K46E had superior methanol conversion efficiency, with 79-, 23-, and 3-fold improvements compared to the wild-type, respectively. These mutant enzymes could thus be useful for engineering synthetic methylotrophy and for enhancing methanol conversion to various useful products.
Topics: Alcohol Oxidoreductases; Bacillaceae; Bacterial Proteins; Biosensing Techniques; Kinetics; Methanol; Mutation
PubMed: 33540582
DOI: 10.3390/ijms22031471 -
Journal of Applied Microbiology Feb 2019To investigate effects of fluoride ion (F ) on, and kinetics of its movement into and out of, spores and growing cells of Bacillus species.
AIMS
To investigate effects of fluoride ion (F ) on, and kinetics of its movement into and out of, spores and growing cells of Bacillus species.
METHODS AND RESULTS
Effects of F on Bacillus cell growth, spore germination and outgrowth and heat resistance were investigated, as well as F movement into and out of spores using F-NMR. F inhibited Bacillus subtilis spore germination and outgrowth, and YhdU, now named FluC, was crucial to prevent F accumulation in growing cells and to minimize F inhibition of spore germination. Dormant wild-type, yhdU and coat defective B. subtilis spores, and Bacillus cereus spores incubated in 40 mmol l NaF for 48 h accumulated 2-2·6 mol l F and its movement into Bacillus spores was highest at low pH. Bacillus subtilis spores lacking Ca-dipicolinic acid accumulated higher F levels than wild-type spores.
CONCLUSIONS
These results are consistent with F incorporation into the dormant spore core, and as HF and/or NaF, but not CaF . YhdU played no significant role in F uptake or efflux in dormant spores, but assisted in F export early in spore germination.
SIGNIFICANCE AND IMPACT OF STUDY
This knowledge provides new insight into effects of F on Bacillus cells and spores and how this anion moves into, and out of spores.
Topics: Bacillus; Bacillus subtilis; Biological Transport; Fluorides; Hot Temperature; Picolinic Acids; Spores, Bacterial
PubMed: 30430725
DOI: 10.1111/jam.14155 -
Microbes and Infection Feb 2000Bacillus cereus is a causative agent in both gastrointestinal and in nongastrointestinal infections. Enterotoxins, emetic toxin (cereulide), hemolysins, and... (Review)
Review
Bacillus cereus is a causative agent in both gastrointestinal and in nongastrointestinal infections. Enterotoxins, emetic toxin (cereulide), hemolysins, and phoshpolipase C as well as many enzymes such as beta-lactamases, proteases and collagenases are known as potential virulence factors of B. cereus. A special surface structure of B. cereus cells, the S-layer, has a significant role in the adhesion to host cells, in phagocytosis and in increased radiation resistance. Interest in B. cereus has been growing lately because it seems that B. cereus-related diseases, in particular food poisonings, are growing in number.
Topics: Animals; Bacillaceae Infections; Bacillus cereus; Bacterial Adhesion; Bacterial Proteins; Gastrointestinal Diseases; Humans; Membrane Glycoproteins; Phagocytosis; Virulence
PubMed: 10742691
DOI: 10.1016/s1286-4579(00)00269-0 -
PeerJ 2023genus has been used in horticultural crops as a biocontrol agent against insect pests, microbial phytopathogens, and plant growth-promoting bacteria (PGPB),...
BACKGROUND
genus has been used in horticultural crops as a biocontrol agent against insect pests, microbial phytopathogens, and plant growth-promoting bacteria (PGPB), representing an alternative to agrochemicals. In particular, (Bc) and (Bt) have been studied for their fungicidal and insecticidal activities. However, their use as biofertilizer formulations and biocontrol agents against phytopathogenic bacteria is limited.
OBJECTIVE
To evaluate Bc and Bt formulations as PGPB and biocontrol agents against the bacterial spot agent (Xe) in greenhouse-grown chili peppers.
METHODS
Bc and Bt isolates obtained from soil samples were identified and characterized using conventional biochemical and multiplex PCR identification methods. Bioassays to determine Bc and Bt isolates potential as PGPB were evaluated on chili pepper seedlings in seedbeds. In addition, formulations based on Bc (F-BC26 and F-BC08) and Bt (F-BT24) strains were assessed as biofertilizers on pepper, under controlled conditions. Furthermore, antagonism assays were performed by confronting Bc and Bt isolate formulations against Xe isolates in direct (foliage) and indirect (resistance induction) phytopathogen biocontrol assays on pepper plants, which were grown under controlled conditions for 15 d after formulations treatment.
RESULTS
Isolates were identified as Bc and Bt. Formulations significantly improved pepper growth in seedbeds and pots, whereas bioassays demonstrated the bactericidal effect of Bc and Bt strains against Xe isolates. Furthermore, assays showed significant plant protection by F-BC26, F-BC08, and F-BT24 formulated strains against Xe.
CONCLUSION
Results indicated that F-BT24 and F-BC26 isolates formulations promoted pepper growth and protected it against .
Topics: Bacillus cereus; Bacillus thuringiensis; Bacillus; Crops, Agricultural
PubMed: 36710864
DOI: 10.7717/peerj.14633 -
Scientific Reports Mar 2018We previously developed an industrial production process for novel water-soluble indigestible polysaccharides (resistant glucan mixture, RGM). During the process, an...
We previously developed an industrial production process for novel water-soluble indigestible polysaccharides (resistant glucan mixture, RGM). During the process, an anhydrosugar-levoglucosan -is formed as a by-product and needs to be removed to manufacture a complete non-calorie product. Here, we attempted to isolate thermophilic bacteria that utilize levoglucosan as a sole carbon source, to establish a removing process for levoglucosan at higher temperature. Approximately 800 natural samples were used to isolate levoglucosan-utilizing microorganisms. Interestingly, levoglucosan-utilizing microorganisms-most of which were filamentous fungi or yeasts-could be isolated from almost all samples at 25°C. We isolated three thermophilic bacteria that grew well on levoglucosan medium at 60°C. Two of them and the other were identified as Bacillus smithii and Parageobacillus thermoglucosidasius, respectively, by 16S rDNA sequence analysis. Using B. smithii S-2701M, which showed best growth on levoglucosan, glucose and levoglucosan in 5% (wt/vol) RGM were completely diminished at 50°C for 144 h. These bacteria are known to have a biotechnological potential, given that they can ferment a range of carbon sources. This is the first report in the utilization of levoglucosan by these thermophiles, suggesting that our results expand their biotechnological potential for the unutilized carbon resources.
Topics: Bacillaceae; Carbon; Cluster Analysis; Culture Media; DNA, Bacterial; DNA, Ribosomal; Glucose; Hot Temperature; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 29511307
DOI: 10.1038/s41598-018-22496-2 -
PloS One 2020Demand for agricultural crop continues to escalate in response to increasing population and damage of prime cropland for cultivation. Research interest is diverted to...
Demand for agricultural crop continues to escalate in response to increasing population and damage of prime cropland for cultivation. Research interest is diverted to utilize soils with marginal plant production. Moisture stress has negative impact on crop growth and productivity. The plant growth promoting rhizobacteria (PGPR) and plant growth regulators (PGR) are vital for plant developmental process under moisture stress. The current study was carried out to investigate the effect of PGPR and PGRs (Salicylic acid and Putrescine) on the physiological activities of chickpea grown in sandy soil. The bacterial isolates were characterized based on biochemical characters including Gram-staining, P-solubilisation, antibacterial and antifungal activities and catalases and oxidases activities and were also screened for the production of indole-3-acetic acid (IAA), hydrogen cyanide (HCN) and ammonia (NH3). The bacterial strains were identified as Bacillus subtilis, Bacillus thuringiensis and Bacillus megaterium based on the results of 16S-rRNA gene sequencing. Chickpea seeds of two varieties (Punjab Noor-2009 and 93127) differing in sensitivity to drought were soaked for 3 h before sowing in fresh grown cultures of isolates. Both the PGRs were applied (150 mg/L), as foliar spray on 20 days old seedlings of chickpea. Moisture stress significantly reduced the physiological parameters but the inoculation of PGPR and PGR treatment effectively ameliorated the adverse effects of moisture stress. The result showed that chickpea plants treated with PGPR and PGR significantly enhanced the chlorophyll, protein and sugar contents. Shoot and root fresh (81%) and dry weights (77%) were also enhanced significantly in the treated plants. Leaf proline content, lipid peroxidation and antioxidant enzymes (CAT, APOX, POD and SOD) were increased in reaction to drought stress but decreased due to PGPR. The plant height (61%), grain weight (41%), number of nodules (78%) and pod (88%), plant yield (76%), pod weight (53%) and total biomass (54%) were higher in PGPR and PGR treated chickpea plants grown in sandy soil. It is concluded from the present study that the integrative use of PGPR and PGRs is a promising method and eco-friendly strategy for increasing drought tolerance in crop plants.
Topics: Agriculture; Ammonia; Bacillaceae; Bacillus megaterium; Bacillus subtilis; Biomass; Chlorophyll; Cicer; Indoleacetic Acids; Lipid Peroxidation; Plant Growth Regulators; Plant Leaves; Plant Proteins; Plant Roots; Putrescine; RNA, Ribosomal, 16S; Rain; Salicylic Acid; Seedlings; Soil Microbiology
PubMed: 32271848
DOI: 10.1371/journal.pone.0231426 -
Microbiology and Molecular Biology... Dec 2015Much of what we know regarding bacterial spore structure and function has been learned from studies of the genetically well-characterized bacterium Bacillus subtilis.... (Review)
Review
Much of what we know regarding bacterial spore structure and function has been learned from studies of the genetically well-characterized bacterium Bacillus subtilis. Molecular aspects of spore structure, assembly, and function are well defined. However, certain bacteria produce spores with an outer spore layer, the exosporium, which is not present on B. subtilis spores. Our understanding of the composition and biological functions of the exosporium layer is much more limited than that of other aspects of the spore. Because the bacterial spore surface is important for the spore's interactions with the environment, as well as being the site of interaction of the spore with the host's innate immune system in the case of spore-forming bacterial pathogens, the exosporium is worthy of continued investigation. Recent exosporium studies have focused largely on members of the Bacillus cereus family, principally Bacillus anthracis and Bacillus cereus. Our understanding of the composition of the exosporium, the pathway of its assembly, and its role in spore biology is now coming into sharper focus. This review expands on a 2007 review of spore surface layers which provided an excellent conceptual framework of exosporium structure and function (A. O. Henriques and C. P. Moran, Jr., Annu Rev Microbiol 61:555-588, 2007, http://dx.doi.org/10.1146/annurev.micro.61.080706.093224). That review began a process of considering outer spore layers as an integrated, multilayered structure rather than simply regarding the outer spore components as independent parts.
Topics: Animals; Bacillaceae Infections; Bacillus; Bacterial Proteins; Clostridium; Clostridium Infections; Host-Pathogen Interactions; Humans; Spores, Bacterial
PubMed: 26512126
DOI: 10.1128/MMBR.00050-15 -
Molecules (Basel, Switzerland) Dec 2021Resistance to antifungal agents represents a major clinical challenge, leading to high morbidity and mortality rates, especially in immunocompromised patients. In this...
Resistance to antifungal agents represents a major clinical challenge, leading to high morbidity and mortality rates, especially in immunocompromised patients. In this study, we screened soil bacterial isolates for the capability of producing metabolites with antifungal activities via the cross-streak and agar cup-plate methods. One isolate, coded S6, showed observable antifungal activity against ATCC 10231 and clinical isolate. This strain was identified using a combined approach of phenotypic and molecular techniques as sp. MK212927. The purified metabolite displayed fungicidal activity, reserved its activity in a relatively wide range of temperatures (up to 60 °C) and pH values (6-7.8) and was stable in the presence of various enzymes and detergents. As compared to fluconazole, miconazole and Lamisil, the minimum inhibitory concentration of the metabolite that showed 90% inhibition of the growth (MIC) was equivalent to that of Lamisil, half of miconazole and one fourth of fluconazole. Using different spectroscopic techniques such as FTIR, UV spectroscopy, 1D NMR and 2D NMR techniques, the purified metabolite was identified as terbinafine, an allylamine antifungal agent. It is deemed necessary to note that this is the first report of terbinafine production by sp. MK212927, a fast-growing microbial source, with relatively high yield and that is subject to potential optimization for industrial production capabilities.
Topics: Antifungal Agents; Bacillaceae; Biological Products; Humans; Microbial Sensitivity Tests; Phylogeny; Soil Microbiology; Spectrum Analysis; Terbinafine
PubMed: 35011429
DOI: 10.3390/molecules27010201